Laboratory Protocols for Investigating Microbial Souring and Potential Treatments in Crude Oil Reservoirs

Oilfield souring is most frequently caused by the activities of sulfate-reducing microorganisms as they reduce sulfate to sulfide as their terminal electron-accepting process. Souring poses serious health and safety hazards to oilfield workers and can be detrimental to oil production processes by potentially plugging reservoirs and/or leading to infrastructure corrosion. Oilfield souring often occurs during secondary recovery operations based on waterflooding, especially when the water source contains an ample amount of sulfate that can stimulate sulfate reducers associated with the reservoir or other locations within an oil recovery operation (such as topside facilities). Water chemistry, temperature, potential carbon sources, and microbial communities all play a role in determining whether souring will occur in a given field. Approaches such as biocide, nitrate, or, most recently, perchlorate treatments have shown good success in controlling souring in laboratory experiments and/or in field applications. This chapter outlines a variety of protocols that can be used in a laboratory setting to study souring potential in a given oilfield and to test methods of souring control that may be applied to that field or oilfields in general. Methods of field sample collection, water chemistry analyses, microbiological analyses, and laboratory incubation strategies are described.
Source: Springer protocols feed by Microbiology - Category: Microbiology Source Type: news